Heat dissipation is a requirement to meet for many electronic devices. Extra heat is generated during the operation of the electronic device, and overheat would affect the performance and reliability of the electronic device. A heat pipe or a heat sink is frequently used as an element for dissipating the extra heat, such that the electronic device would not be overheated. Heat transfer may occur by the mechanisms of conduction, convection and radiation.
The mechanism of conduction or convection is adopted for a traditional heat sink to achieve the purpose of heat dissipation. However, the current electronic device tends to become miniaturization. The space and weight are limited especially for a portable electronic device, such that many known heat sinks cannot be designed in such device.
The technology using the mechanism of radiation has been developed to meet the heat dissipation requirement for the current electric device. A layer of heat radiation coating material or nano-size powder is applied to the heat source surface to dissipate heat efficiently by heat radiation. Due to the limited space and volume of the current electric device, the best way for cooling the object surface is by heat radiation, and the heat is released to the external environment in the form of infrared ray. When the object has a temperature higher than the ambient temperature, heat can be released to the environment by radiation.